Methods and apparatus for performing minimally invasive surgery

ABSTRACT

A device for expanding an elongate opening formed in a skin layer of a patient includes a first arm for engaging one side of the opening and a second arm for engaging the other side of the opening. The device further includes a spreader mechanism, coupled to at least one of the first and second arms, to move the at least one of the first and second arms to widen the opening. The at least one arm is configured to move between a retracted position in which the at least one arm is positioned next to the other arm and an extended position in which the at least one arm is extended to expand the opening. Other embodiments of the device as well as methods for performing a medical procedure are further disclosed.

RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/692,139, entitled “METHODS AND APPARATUS FOR PERFORMING MINIMALLYINVASIVE SURGERY”, filed on Jan. 22, 2010, which is acontinuation-in-part of U.S. patent application Ser. No. 11/370,250,entitled “METHODS AND APPARATUS FOR PERFORMING MINIMALLY INVASIVESURGERY, filed on Mar. 7, 2006 [now U.S. Pat. No. 7,651,465], whichclaims priority to U.S. Provisional Application Ser. No. 60/659,303,entitled “METHODS AND APPARATUS FOR PERFORMING MINIMALLY INVASIVESURGERY,” filed on Mar. 7, 2005 [now Abandoned], all of which are hereinincorporated by reference in their entirety.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

This disclosure relates generally to methods and devices for performingsurgery, and more particularly, to methods and devices for performingminimally invasive surgery, such as cardiac surgery, including, but notlimited to, coronary artery bypass grafting, valvular, dysrhythmia andaortic surgery, as well as thoracic surgical procedures.

2. Discussion of Related Art

Coronary artery disease is the largest or one of the largest causes ofdeath in the United States. Interventions for coronary artery diseaseinclude education, medication, percutaneous coronary intervention, suchas balloon angioplasty and stenting, and coronary bypass surgery.

Coronary artery bypass surgery is the most common type of heart surgery,with over 300,000 people having successful surgery in the United Stateseach year. As is well known, arteries can become clogged over time bythe build-up of fatty plaque in the artery wall. Coronary bypass surgerybypasses the diseased artery with a new blood vessel taken from the leg(greater saphenous vein) or an artery from the chest or arm. Thisprocedure creates a new route for blood to flow.

Coronary artery bypass surgery is typically performed through an openchest exposure (i.e., to access and circumvent obstructed coronaryarteries). A common approach involves making a 15-20 cm long incision inthe skin overlying the breastbone, and splitting and separating thesternum to provide full access to the heart. With reference to FIG. 1,during coronary artery bypass surgery, the patient's breastbone 10(sternum) is divided by means of a sternal saw. As stated above, atypical incision 12 is approximately 15-20 cm long. After appropriatebypass conduits are taken (e.g., a vein from the patient's leg), asternal retractor is placed to spread the skin and breastbone to exposethe heart and vessels for the bypass procedure. During the procedure,the heart may be stopped, and the patient's blood is sent through aheart-lung machine. This procedure typically takes three to five hoursto perform, depending on the number of bypasses required. Three to foursmaller incisions may be made inferior to the initial incision for drainplacement around the heart after the procedure is completed. At the endof the procedure, the patient's breastbone is wired back together andthe muscle and skin are closed as well with absorbable sutures.

The long incision 12 described above, which starts from the very top ofthe breastbone and extends the bottom of the breastbone, cuts not onlythe breastbone, but tissue and muscle as well. During the operation, asternal retractor is situated above the cavity to spread the skin,tissue, muscle and breastbone. This large incision may cause severalpotential negative side effects. Of all the layers of body tissue, theskin is the most innervated with sensory nerves, as compared to muscleand breastbone. Further, closure of the pectoral muscles must be done ina fashion that results in much more tension on the muscles than thenative state. This may result in extreme pain at rest which isexacerbated by any action that stretches the skin or muscle, which canlead to respiratory complications and general inactivity due tosplinting. There may also be associated negative psychological effects.

Experience from other surgical procedures has shown that minimizedsurgical incisions result in shorter intensive care unit and hospitalstays, less complications, less pain, and an overall better experiencefor the patient. For example, prior techniques in gallbladder removal(cholecystectomy) involved a substantial incision of 12-15 cm in theabdomen, which results in expected increased patient discomfort. Whenlaparoscopic cholecystectomy was developed, which involves making foursmall incisions (each between 0.5 and 1.2 cm long) and the use of videoequipment, the results was shorter hospital stays, less complicationsand quicker patient recovery.

Percutaneous coronary intervention (“PCI”) was developed as a lessinvasive way than coronary artery bypass grafting to treat coronaryartery disease. PCI has progressed from balloon angioplasty, to stents,to drug eluting stents. However, PCI may not be suitable for patientswho are diabetic or who have three or more artery blockages, accordingto the official recommendations of the American College of Cardiology.

Although there are examples of “minimal” invasive coronary artery bypasssurgery, such surgery typically involves bypassing only left sided,anterior coronary vessels, through a limited rib spreading incision.This operation is only used for patients whose entire set of blockagescan be bypassed through this smaller incision which represents aminority of patients.

Minimally invasive approaches to all types of operations are desirablebecause of the advantages of less scarring and pain, shorter hospitalstays and recovery time. With minimally invasive approaches, suchapproaches generally try to avoid splitting the sternum and may use aseries of incisions to gain adequate visualization and access thepatient's heart. Rarely, with these approaches, is it possible to usevideoscopic imaging systems or robotic guidance devices. While thesetechniques may provide advantages when dealing with a limited set ofanatomic heart problems, they are not widely adopted due to theircumbersome nature, and the limited mobility through relatively fixedbony and muscular structures. There is concern that sub-par results maybe obtained. In addition with small incisions, reduced three-dimensionalvisibility and perceptual orientation may increase some risk to thepatient.

SUMMARY OF THE DISCLOSURE

One aspect of the disclosure is directed to a method of performingcoronary artery bypass and other open heart procedures. The methodcomprises: making at least one small incision of approximately 5 cmabove the breastbone of the patient, with or without mobilizing thesternal envelope (fascia) in order to spare division of the pectoralmuscles; dividing the entire breastbone to create an opening; insertinga device within the opening below the skin (and possibly, muscle) layer;expanding the device to increase the opening; performing a medicalprocedure; retracting the device; and closing the opening.

Another aspect of the disclosure is directed to a device for expandingan opening within a patient having a length of 5 cm or less. The devicecomprises a central body, and at least one arm coupled to the body. Thearm is adapted to move between a retracted position in which the arm ishoused within the central body and an extended position in which the armis extended to expand the opening.

Yet another aspect of the disclosure is directed to a method ofperforming a medical procedure. The method comprises: making an incisionin a patient; inserting a device through the incision and below a skinlayer; expanding the device to expand an opening below the skin layer;and performing the medical procedure. In one embodiment, the opening isa division in the breastbone of a patient. The medical procedure mayinclude pectoralis-sparing open heart surgery.

A further aspect of the disclosure is directed to a device for expandingan elongate opening formed in a skin layer of a patient, with theopening having opposite sides. The device comprises a first arm forengaging one side of the opening, a second arm for engaging the otherside of the opening, and a spreader mechanism, coupled to at least oneof the first and second arms, to move the at least one of the first andsecond arms to widen the opening. The at least one arm is adapted tomove between a retracted position in which the at least one arm ispositioned next to the other arm and an extended position in which theat least one arm is extended to expand the opening.

Embodiments of the device may further include the first and second armscomprising a distracter shaft and a support channel releasably securedto the distracter shaft. The support channel may be configured to engagea side of the opening. The support channel may further include aC-shaped surface adapted engage body tissue below the skin layer towiden the opening. The support channel may have a length of less than 5cm. The support channel may have a wedge-shaped leading edge. In oneembodiment, one of the first and second arms comprises an actuatormember coupled to the spreader mechanism. The spreader mechanismcomprises a gear box and a device for turning the gear box. The gear boxcomprises a first gear segment secured to the actuator member of thefirst arm and a gear wheel to engage the first and second gear segments.The gear box may further comprise a second gear segment secured to theactuator member of the second arm. A mount may be formed on the spreadermechanism, the mount being configured to secure the device to a supportassembly. In another assembly, the spreader mechanism may comprise ascissor mechanism.

Another aspect of the disclosure is directed to a method of performingan open heart surgery procedure. The method comprises: making at leastone small incision of approximately 5 cm above a breastbone of thepatient; dividing the breastbone to create an opening; inserting adevice within the opening below a skin layer; expanding the device toincrease the opening; performing a medical procedure; retracting thedevice; and closing the opening. In one embodiment, the step ofexpanding the device includes moving at least one arm of the device towiden the opening.

Another aspect of the disclosure is directed to a device for expandingan elongate opening formed in a skin layer of a patient, with theopening having opposite sides. The device comprises a first arm forengaging one side of the opening and a second arm for engaging the otherside of the opening. The first and second arms are configured to engagethe sides of the opening below the skin layer. The device furthercomprises means for moving at least one of the first and second arms forwidening the opening. The at least one arm is adapted to move between aretracted position in which the at least one arm is positioned next tothe other arm and an extended position in which the at least one arm isextended to expand the opening. In one embodiment, the means for movingat least one of the first and second arms comprises a spreadingmechanism disposed above the skin layer and coupled to the at least oneof the first and second arms.

An additional aspect of the disclosure is directed to a method ofperforming a medical procedure. The method comprises: making an incisionin a patient; inserting a device below the skin layer of the patient;expanding the device to expand an opening below the skin layer; andperforming the medical procedure. In one embodiment, the opening is adivision in the breastbone of a patient. In another embodiment themedical procedure is pectoralis-sparing open heart surgery.

Another aspect of the disclosure is directed to a device for expandingan opening formed below a skin layer of a patient, with the openinghaving opposite sides. In one embodiment, the device includes a firstL-shaped member having a first arm and a first actuator connected to thefirst arm. The first arm of the first L-shaped member is configured toengage one side of the opening. The device further includes a secondL-shaped member having a second arm and a second actuator connected tothe second arm. The second arm of the second L-shaped member isconfigured to engage the other side of the opening. The first L-shapedmember is configured to nest within the second L-shaped member with bothmembers maintaining a generally identical orientation. The devicefurther includes a spreader mechanism, coupled to at least one of thefirst and second actuator members, to move the first and second armsapart from one another. The first and second arms are configured to movebetween a retracted position in which the first and second arms arepositioned next to one another and an extended position in which thefirst and second arms are extended to expand the opening.

Embodiments of the device may include configuring each of the first andsecond arms with a distracter shaft and a support channel releasablysecured to the distracter shaft. The support channel is configured toengage a side of the opening. The support channel may include a C-shapedsurface adapted to engage body tissue below the skin layer to widen theopening. The arrangement is such that arms of the device may be insertedthrough at least one site that is separate from a skin incision. Thedevice may be configured to spread apart the opening without directlyspreading apart edges of the skin layer. In one embodiment, at least onearm or support channel includes an illumination element configured todirect light below the device when viewed from above. The spreadermechanism may include a gear box and a device for turning the gear box.

A further aspect of the disclosure is directed to a device for expandingan opening formed below a skin layer of a patient, with the openinghaving opposite sides. In one embodiment, the device includes a firstarm for engaging one side of the opening, a second arm for engaging theother side of the opening, a first actuator member connected to thefirst arm, and a second actuator member connected to the second arm. Thefirst arm includes a segment that overlays the second actuator member.The device further includes a spreader mechanism, coupled to at leastone of the first and second actuator members, to move the arms aparthorizontally. The arms are adapted to move between a retracted positionin which the arms are positioned next to one another and an extendedposition in which the arms are extended to expand the opening.

Another aspect of the disclosure is directed to a device for expandingan opening formed below a skin layer of a patient, with the openinghaving opposite sides. In one embodiment, the device includes a firstarm for engaging one side of the opening, a second arm for engaging theother side of the opening, a first actuator member attached to orreversibly attachable to the first arm, a second actuator memberattached to or reversibly attachable to the second arm, a first spreadermechanism configured to be attached to an operating table and coupled tothe first actuator member, and a second spreader mechanism configured tobe attached to an operating table and coupled to the second actuatormember. The first and second spreader mechanisms are configured to movethe first and second arms apart. The first and second arms are adaptedto move between a retracted position in which the arms are positionednext to one another and an extended position in which the arms areextended to expand the opening.

Embodiments of the device may include providing the first and secondspreader mechanisms with a cable and pulley system to move the first andsecond actuator members. The first and second spreader mechanisms mayinclude a rack and pinion assembly to move the first and second actuatormembers.

Yet another aspect of the disclosure is directed to a device forexpanding an opening formed below a skin layer of a patient, with theopening having opposite sides. In one embodiment, the device includes afirst arm for engaging one side of the opening and a second arm forengaging the other side of the opening. The first arm is attached to abase and the second arm is attached to an actuator that traversesthrough the base. The device further includes a crankshaft attached toor reversibly coupled to one of the actuator and the base and a spreadermechanism, actuated by the crankshaft, to move the first and second armsapart. The arms are adapted to move between a retracted position inwhich the arms are positioned next to one another and an extendedposition in which the arms are extended to expand the opening.

Another aspect of the disclosure is directed to a method for performingsurgery on organs located below a skin and muscle layer through a smallskin incision. The method comprises: making a small access incision inthe skin; surgically separating a tissue plane between a normallyadherent and adjacently layered muscle and fatty tissue radiatingoutward from the skin; utilizing a device to spread divided deepertissues apart below the level of the skin without directly contactingthe skin edges of the access incision; and performing a surgicalprocedure. In one embodiment, the small access incision is generallyless than 8 cm long. The device may be configured with a crankshaftdriver that traverses from external to, to internal to, the skin inorder to actuate and spread the device apart below the intact skinadjacent to the access incision.

A further aspect of the disclosure is directed to a method forperforming heart surgery through a small skin incision comprising:making a small access incision in the skin overlying the breastbone;surgically separating a tissue plane between the normally adherent andadjacently layered pectoralis muscle and fatty tissue radiating outwardfrom the skin incision underneath adjacent areas of intact skin;dividing the pectoralis muscles and the breastbone vertically in themidline; utilizing a device to spread apart the breastbone below thelevel of the skin without directly contacting the skin edges of theaccess incision; and performing heart surgery. In one embodiment, thesmall access incision is generally less than 8 cm long. The device maybe configured with a crankshaft driver that traverses from external to,to internal to, the skin in order to actuate and spread the device apartbelow the intact skin adjacent to the access incision.

Yet another aspect of the disclosure is directed to a method forinstructing a surgeon to perform heart surgery through a small skinincision comprising: directing the surgeon to create a small accessincision in the skin overlying the breastbone; surgically separating thetissue plane between the normally adherent and adjacently layeredpectoralis muscle and fatty tissue radiating outward from the skinincision underneath adjacent areas of intact skin; dividing thepectoralis muscles and the breastbone vertically in the midline;utilizing a device to spread apart the breastbone below the level of theskin without directly contacting the skin edges of the access incision;and performing heart surgery. In one embodiment, the surgeon is furtherinstructed to actuate the device by utilizing a crankshaft driver thattraverses from external to, to internal to, the skin.

One additional aspect of the disclosure is directed to a method forinstructing a surgeon to perform surgery through a small skin incisioncomprising: directing the surgeon to create a small access incision inthe skin overlying the region of interest; surgically separating thetissue plane between the normally adherent and adjacently layered muscleand fatty tissue radiating outward from the skin incision underneathadjacent areas of intact skin; dividing the muscle layer; and utilizinga device to spread apart the deeper tissues below the level of the skinwithout directly contacting the skin edges of the access incision, andperforming a surgical procedure. In one embodiment, the surgeon isfurther instructed to actuate the device by utilizing a crankshaftdriver that traverses from external to, to internal to, the skin.

The present disclosure will be more fully understood after a review ofthe following drawing figures, detailed description and claims.

DESCRIPTION OF THE DRAWINGS

For a better understanding of the present disclosure, reference is madeto the drawing figures which are incorporated herein by reference and inwhich:

FIG. 1 is a representation of incisions made on a patient pursuant to aprior method of performing coronary artery surgery;

FIG. 2 is a representation of incisions made on a patient pursuant to amethod of an embodiment of the disclosure for performing coronary arterysurgery;

FIG. 3 is a block diagram showing a method of an embodiment of thedisclosure for performing coronary artery surgery;

FIG. 4A is a schematic representation of a device of an embodiment ofthe disclosure for performing a method of coronary artery surgery, witharms of the device being shown in a retracted position;

FIG. 4B is a schematic representation of the device shown in FIG. 4A,showing the arms of the device in an extended position;

FIG. 5 is a perspective view of a device of another embodiment of thedisclosure for performing a method of coronary artery surgery, with armsof the device being shown in a retracted position;

FIG. 6 is a perspective view of the device shown in FIG. 5, showing thearms of the device in an extended position;

FIG. 7 is a perspective view of the device shown in FIGS. 5 and 6, witha operating mechanism being attached to actuating arms of the device andbreastbone support channels being unattached to distracter shafts of thedevice;

FIG. 8 is a perspective view of the device shown in FIG. 7, showing thebreastbone support channels being attached to the distracter shafts andin a retracted position;

FIG. 9 is a perspective view of the device shown in FIG. 8, with thearms of the device being shown in an extended position;

FIG. 10 is a perspective view of a gear box of the operating mechanismshown in FIGS. 7-9;

FIG. 11 is a perspective view a device of yet another embodiment of thedisclosure for performing a method of coronary artery surgery, with armsof the device being shown in a retracted position;

FIG. 12 is a perspective view of the device shown in FIG. 11, showingthe arms of the device in an extended position

FIG. 13 is a bottom perspective view of the device shown in FIGS. 11 and12 showing the device mounted on a support assembly;

FIG. 14 is a top perspective view of the device shown in FIG. 13;

FIG. 15 is a cross-sectional view of a patient's breastbone beingdivided by a device of embodiments of the present disclosure;

FIGS. 16 and 16A are side elevational views of components of a device ofanother embodiment of the disclosure;

FIG. 17 is a perspective view of an arm of a device of anotherembodiment of the disclosure with a segment of the arm overlaying anactuator;

FIG. 18 is a perspective view of an embodiment of a device showing twospreader mechanisms attached to opposite sides of an operating roomtable that operate two winches;

FIGS. 19 and 19A are exploded perspective views of an embodiment of adevice having a crankshaft that is used to operate a nut-and-boltmechanism to spread arms of the device apart;

FIGS. 20 and 20A are exploded perspective views of another embodiment ofa device having two spreader mechanisms that are attached to oppositesides of an operating room table utilizing a rack-and-pinion mechanismto spread arms of the device apart;

FIGS. 21 and 21A are another embodiment of a device having a crankshaftthat is used to turn gears that interact with an actuator in arack-and-pinion mechanism to spread arms of the device apart;

FIG. 22 illustrates an exploded perspective view of a device of thedisclosure having arms or support channels that contain an integratedlight panel;

FIGS. 23 and 23A illustrate initial steps of a method of performingsurgery through a small skin incision;

FIGS. 24 and 24A illustrate initiation of a surgical dissection planebetween adjacent and overlying muscle and fatty tissue layers;

FIGS. 25 and 25A illustrate creation of an extended tissue plane andspace between the muscle and fatty tissue layers through a small accessincision in the skin and fatty tissue;

FIGS. 26 and 26A illustrate division of muscle within an extended spacecreated by surgical dissection, thereby exposing the underlyingbreastbone;

FIGS. 27 and 27A illustrate division of the breastbone with a jigsawthrough the small access incision;

FIG. 28 illustrates a completely divided breastbone underneath thelargely intact skin and fatty tissue block;

FIG. 29 illustrates insertion of arms of a device through a smallerincision or incisions distinct from the access incision, and advancingthem towards the access incision;

FIGS. 30 and 30A are enlarged views showing reversibly attachablesupport channels of a device being joined to the arms of the device viathe small access incision;

FIGS. 31 and 31A illustrate stages of a device being deployed, and thearms of the device gradually extending apart the divided breastboneedges;

FIG. 32 illustrates a device in a fully deployed state, spreading apartthe breastbone extensively underneath the largely intact skin and fattytissue;

FIG. 33 illustrates the device shown in FIG. 19 in an extended position,with the device fully inserted below the skin and fatty tissue layersafter creation of that space, and with a crankshaft being insertedthrough a separate stab incision distinct from the access incision inorder to actuate the device to spread its arms apart; and

FIG. 34 illustrates a device of another embodiment of the disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

This disclosure is not limited in its application to the details ofconstruction and the arrangement of components set forth in thefollowing description or illustrated in the drawings. The disclosure iscapable of other embodiments and of being practiced or of being carriedout in various ways. Also, the phraseology and terminology used hereinis for the purpose of description and should not be regarded aslimiting. The use of “including,” “comprising,” or “having,”“containing,” “involving,” and variations thereof herein, is meant toencompass the items listed thereafter and equivalents thereof as well asadditional items.

Generally, coronary artery bypass grafting procedures are performed oneof two ways—beating heart surgery and non-beating heart surgery. Thenon-beating heart procedure uses a heart-lung cardiopulmonary bypassmachine, in which the heart is purposely arrested (stopped) and thepatient's blood is recycled and oxygenated by the machine. Beating heartsurgery (also known as “off-pump” coronary bypass surgery) was performedbefore non-beating heart surgery and has recently been rejuvenated as amodern technique.

With reference to FIG. 2, a method according to one embodiment of thedisclosure involves making a small incision, in an average size adultpatient, of approximately 4-5 cm over the sternum and another crossincision of approximately 2 cm below the sternal notch. This method maybe employed to perform pectoralis-sparing, minimally invasive coronaryartery bypass surgery. As mentioned above, a first, vertically orientedsmall incision 20 is made in the lower third of the skin overlying thesternum, approximately 4-5 cm in length (the “working” incision). Thefirst incision 20 is taken down to the level of the sternum 10 and thesternal envelope (investing fascia) is mobilized on the anterior surfaceusing a combination of electrocautery and blunt dissection. Themobilization is carried out laterally with partial mobilization of thepectoralis muscle off of the chest wall. A second, horizontally orientedsmall incision 22 of approximately 2-3 cm horizontal is made just belowthe sternal notch (junction of the neck with the chest). This secondincision 22 is used initially to help complete mobilization of theaforementioned tissues in the well-known manner. Once mobilization iscomplete, division of the sternum 10 is accomplished with a standardjigsaw using both incisions.

A mammary retractor may be used through the working incision 20 andbelow the skin to lift the left and/or right hemi-sternum in order toperform mammary artery pedicle harvesting using standard techniques, butthrough this small incision. For example, the mammary artery harvest mayinclude adjunctive video assistance. Devices used to perform the methodwill be discussed in greater detail below with references to FIGS. 4-14.

In an embodiment of a method of the disclosure, with reference to FIG.3, a method of performing coronary artery bypass surgery, generallyindicated at 40, is disclosed. A first small incision (e.g., 4-5 cm inlength) is made to separate the patient's breastbone. A second smallincision (e.g., 2 cm) is made horizontally just below the sternal notch.The incisions are indicated by step 42 in FIG. 3. Once mobilization iscomplete, the division of the sternum is achieved by standardtechniques, e.g., by using a jigsaw (step 44).

A device, such as a retractor of embodiments of the present disclosure,is inserted into the cavity between the divided breastbone, as indicatedby step 46 in FIG. 3. The device is manipulated below the skin layer toexpand the opening to a distance sufficient to perform a medicalprocedure, such as coronary artery bypass surgery (step 48). In oneembodiment, the breastbone may be expanded up to 20 cm.

Once opened, the medical procedure may be performed (step 50) via theopening. As disclosed herein, the retractor is especially suited forperforming coronary artery bypass surgery. However, other procedures arecontemplated, and may include, but are not limited to, bypass surgery,valvular and dysrhythmia surgeries and other procedures performed withinthe chest cavity. It should be understood that the methods and devicesdisclosed herein, may be applied to perform procedures at otherlocations within the body, e.g., the thorax or abdomen.

Once the procedure is performed, the device is retracted (step 52) andremoved (step 54). At this point, the cavity defined by the opening maybe appropriately closed (step 56) by wiring the breastbone and suturingthe muscles and skin above the breastbone.

With reference to FIGS. 4A and 4B, a retractor of an embodiment of thedisclosure, generally indicated at 30, is designed so that its mechanismof retraction is under the level of the skin, as opposed to conventionalretractors, which are typically placed on top of the sternum, and whosespreading mechanism is above the level of the dermis. A separate crank(not shown) may be placed through a different 1 cm stab incision 24(FIG. 2) below the main working incision 20 to actuate the spreadingmechanism. This stab incision 24 is in the location of one of thetypical sites of chest drain placement after coronary artery bypasssurgery, and may ultimately be utilized for such a drain. Three or fourof these 1 cm stab incisions 24 may be made as illustrated to FIG. 2,all in positions of future drain sites. Once the sternum is spread tothe standard width, the formal coronary artery bypass procedure isinitiated.

The retractor 30 of an embodiment of the disclosure differs from priorretractors in its operable components are configured to be seated belowthe level of the dermis, mobilized pectoralis muscle, or the breastboneitself. The retractor 30 is capable of completely separating thebreastbone as with prior retractors; however, the low profile of theretractor enables the retractor to be hidden away from the surgicalfield during the entire surgery.

As shown in FIGS. 4A and 4B, the retractor 30 comprises a central body32 that may be generally rectangular, circular or oval in shape andsized to fit within the incision performed on the patient's breastbone.With reference to FIG. 4B, the central body 32 houses two telescopicarms, each arm indicated at 34, that extend outwardly from the centralbody. As shown, one arm 34 is positioned on one side of the central body32 and the other arm is positioned on the other side of the centralbody. In another embodiment, a separate device may be provided, e.g., aframe, that houses the telescopic arms. Also, although two arms 34 areillustrated in FIG. 4B, the provision of a device having a central bodythat engages one side of the opening and one arm that engages the otherside of the opening, or a device having more than two arms, e.g., fourarms, is contemplated. Provided at the end of each telescopic arm is anend plate 36 that temporarily locks into a platform 38 adapted toconform to the sternal edges or sides of the patient's breastbone. Eachplatform 38 is approximately 5 cm long and is designed to cup thesternal edge in a longitudinal fashion. In this procedure, the centralbody 32 of the retractor 30 lies in a plane parallel to, but 1-2 cmbelow the lowermost plane of the platform 38. Upon extending thetelescopic arms 34, the central body 32 is positioned 5-10 cm away fromoppositely disposed platforms 38.

In an embodiment of the disclosure, the retractor 30 is adapted to slideinto the incision between the divided breastbone. The central body 32 ofthe retractor 30 will lie below the plane of the sternum, but beyond thebottom of the heart towards the diaphragm, which separates the abdomenfrom the chest cavity. The dimensions of the central body 32, in oneembodiment, may be 2 cm by 2 cm in area from top plan view and berectangular, circular or oval in shape. Once in position, the sternum isseparated by moving the telescopic arms 34 outwardly to engage the endplates 36 to their respective platforms 38. In one embodiment, the endplates 36 temporarily lock in place within grooves (not shown) formed inthe platform 38. In this position, a medical procedure, such as cardiacsurgery, may be performed. The minimal size of the retractor 30 enablesthe medical procedure to be performed.

The arrangement is such that when actuating the retractor 30 from abovethe skin incision, the telescopic arms 34 of the retractor extend andlock in place at a desired width of separation. The telescoping actionof the arms 34 is designed to cause the upward angulation of the dividedbreastbone (up to 45° or more), which provides more volume under theincision for manipulation of the heart.

After the operation is complete, drains and pacing wires are placed.Afterwards, the telescopic arms 34 of the retractor 30 are retracted orwithdrawn to within the central body 32 (FIG. 4A) and collapsed to itsminimal size by a release mechanism (not shown) built into the centralbody of the retractor, and the retractor is removed from the patient.

In another embodiment, the device may include a two-part body havingopposite edges arced or otherwise configured to engage opposite sides ofthe divided sternal edges. The device may be manipulated to pull thedivided breastbone apart by, for example, a pair of wires that extendsthrough lateral portions of the patient's chest cavity and is ratchetedto each side of the operating table.

In an embodiment of the disclosure, long needle drivers and forceps areused through the working incision. The thymus is divided and pericardiumopened, and a pericardial well is created, using long needles that arepassed through the skin and underlying muscle. Cannulation sutures areplaced through the working incision while Rommel-type tourniquets arebrought out through the upper counter incision. The aortic cannula isplaced through the upper counter incision and cannulation itself isperformed through the working incision. The tourniquets are tightenedand the cannula is connected to the heart-lung machine. Venouscannulation is carried out using a long cannula through the commonfemoral vein in the groin, preferably using a percutaneous Seldingertechnique or through the right chest into the atrium in the standardfashion. Cardiopulmonary bypass is established. A retrogradecardioplegia cannula and its tourniquet may be placed through one of thefour 1 cm stab incisions (see FIG. 2), and the cannula placed throughthe working incision and positioned by digital palpation. An antegradecardioplegia cannula, its tourniquet, as well as the aortic cross clampmay be placed through the upper counter incision. A left ventricularvent and its tourniquet can be placed through one of the stab incisions,and directed through the working incision. The aorta is dissected awayfrom the pulmonary artery and aortic cross clamping/cardioplegiadelivery is accomplished.

The heart is then mobilized to perform distal coronary anastomoses. Theheart is moved, retracted, and stabilized using deep pericardial suturesor, e.g., sponge stick or other instruments that are brought in throughthe remaining stab incisions. Laparotomy pads may be delivered throughthe working incision and placed behind the heart to aid in mobilization.All coronary targets can be visualized through the working incision, anddissection and anastomoses may be carried out in the standard fashion.Once these are completed, proximal anastomoses are performed on theaorta in the usual way, either with the aortic cross clamp in place, orby replacing the cross clamp with a partial aortic clamp through theupper counter incision. Weaning from cardiopulmonary bypass anddecannulation are completed. After hemostasis is ensured and drains areplaced (and brought out through the stab incisions), the sternum isre-approximated with standard sternal wires through both the working andupper incisions. The upper and working incisions are closed withabsorbable suture in layers.

As can be appreciated, the provision of smaller incisions results inimproved aesthetics and less post-operative pain. Smaller incisions maysignificantly diminish the amount of pain associated with movement,ambulation, coughing and deep breathing. Smaller incisions may also leadto decreased atelectasis (lung segmental collapse) and pleuraleffusions, and other pulmonary complications. The aforementionedbenefits would likely contribute to a shorter hospital stay and lessreliance on health care benefits. Post-operative recovery may besignificantly hastened, and resumption of full activity might bedecreased to approximately 1-2 weeks from 4-6 weeks. Restrictions onactivity may be lightened, because the pectoralis muscle complex hasbeen mobilized off of the chest wall, and there will be significantlyless force placed on the sternal (bone) closure. This may alsopotentially lead to a lower risk of sternal dehiscience (separation). Asmight be appreciated, based on the disclosure herein, some (but not all)embodiments of the present disclosure can address or assist with respectto one or more of the above advantages.

Unknown beneficial attributes of the mesothelial cell lining of theheart and its associated tissues may be protected due to preservation ofhigh levels of humidity because of the minimally invasive approach.Benefits may include less post-op adhesion formation (scarring) thatwould make re-operative cardiac surgery less risky. Similar benefitshave been witnessed after laparoscopic and video-assisted thoracicsurgeries. The prevention of desiccation (drying out) of these tissuesmay have a beneficial effect on the incidence of post-op atrialfibrillation (a heart rhythm disturbance that occurs in one-third ofpost-op cardiac patients and carries significant cost and morbidity). Asmight be appreciated based on the disclosure herein, some (but not all)embodiments of the present disclosure can address or assist with respectto one or more of the above advantages.

Turning now to FIGS. 5 and 6, there is generally indicated at 100 adevice of an embodiment of the disclosure for expanding an opening underthe skin layer of a patient so that a medical procedure, such as cardiacbypass surgery, may be performed. As discussed above, the device 100 isconfigured to fit within and open a small incision (e.g., 4-5 cm inlength) made to separate the patient's breastbone. The device may alsobe used to widen other openings formed in the patient, such as openingsbetween the patient's ribs. The device includes a first arm 102 having adistracter shaft 104 and a support channel 106 that is releasablyattachable to the distracter shaft 104. The device 100 further includesa second arm 108 having a distracter shaft 110 and another breastbonesupport channel 106 that is identical to the breastbone support channel106 used on the first arm 102. The support channels 106 are configuredto engage opposite sides of the opening of the patient (e.g., the leftand right hemi-sternums). As shown in FIG. 5, the first and second arms102, 108 may be positioned in a retracted position in which the arms areadjacent one another. In one embodiment, the first arm 102 may beconfigured to overly the second arm 108. FIG. 6 shows the first andsecond arms 102, 108 in an extended position so as to expand the openingby spreading the left and right hemi-sternums.

In one embodiment, each support channel 106 includes a C-shaped surface112 that is configured to engage the patient's divided breastbone underthe skin layer. Although described to engage a patient's breastbone, theC-shaped surface 112 may be configured to engage other body tissue, suchas a patient's rib. Referring to FIG. 7, each support channel includesan elongate opening 114 formed therein, and is attached to itsrespective arm 102 or 108 by sliding the distracter shaft 104 or 110 ofthe arm through the elongate opening. As shown, each support channel 106includes a wedge-shaped leading edge or nose 116, which generates adividing effect in distracting the breastbone. In a certain embodiment,the support channel 106 is approximately 5 cm long so as to fit withinthe opening of the patient.

Referring now to FIGS. 7-9, and more particularly to FIGS. 8 and 9, thefirst arm 102 is connected to a first actuator member 118 and the secondarm 108 is connected to a second actuator member 120. Each actuatormember 118, 120 is generally a U-shaped structure. The free ends of theactuator members 118, 120 are coupled to a spreader mechanism, generallyindicated at 122, which are adapted to move the actuator members 118,120 with respect to each other. Specifically, the spreader mechanism 122is configured to move the first and second arms 102, 108 via respectiveactuator members 118, 120 between a retracted position in which the armsare positioned next to one another and an extended position in which thearms move away from each other. In other embodiments, the spreadermechanism 122 may be configured to move only one arm, e.g., first arm102, with the other arm, e.g., second arm 108, being fixedly attached tothe spreader mechanism. FIG. 8 shows the first and second arms 102, 108in their retracted position. FIG. 9 shows the first and second arms 102,108 in their extended position. A suitable device, such as a hand crank124, may be provided to move the first and second arms 102, 108 betweentheir retracted and extended positions. In other embodiments, anautomated mechanism may be employed, such as a motorized system, to movethe first and second arms 102, 108. In one embodiment, the extendedposition may widen the opening underneath the skin layer up to 20 cm, ormore without tearing or otherwise harming the skin and muscle layers.

Turning now to FIG. 10, a gear mechanism, generally indicated at 126, isprovided to move the first and second arms 102, 108 between theirretracted and extended positions. As shown, the gear mechanism 126includes a first gear segment 128 attached to the first actuator member118. Similarly, a second gear segment 130 is attached to the secondactuator member 120. A gear wheel 132 is suitably positioned between thefirst and second gear segments 128, 130. The gear wheel 132 is connectedto the hand crank 124 so that upon rotating the hand crank, the gearwheel rotates. The arrangement is such that by rotating the hand crank124, the first and second gear segments 128, 130 move the first andsecond actuator members 118, 120. With the arrangement illustrated inFIG. 10, by rotating the hand crank 124 in a clockwise direction, thefirst and second arms 102, 108 move to their retracted position. Byrotating the hand crank 124 in a counterclockwise direction, the firstand second arms 102, 108 move to their extended position. A suitablecasing 134 (shown in FIGS. 7-9) is provided to house the components ofthe gear mechanism 126.

FIGS. 11 and 12 illustrate a device, generally indicated at 140, ofanother embodiment of the disclosure. As shown, the first and secondarms 102, 108 of the device 140 are configured to be identical to thefirst and second arms 102, 108 of device 100. Device 140 includesstraight actuator members 142, 144, that are connected to first andsecond arms 102, 108, respectively, and a spreader mechanism 146designed to move the first and second arms 102, 108 via actuator members142, 144 between retracted and extended positions. As shown, thespreader mechanism 146 is a scissor-type mechanism in which a knob 148is provided to move the first and second arms 102, 108. FIG. 11 showsthe first and second arms 102, 108 in their retracted position. FIG. 12shows the first and second arms 102, 108 in their extended position towiden the opening. A casing 150 is provided to enclose the components ofthe spreading mechanism 146.

During use, a device, such as device 100 or 140, may be disposed overthe patient so that the arms of the device are positioned underneath thepatient's skin layer and the spreader mechanism is disposed above thepatient. Since the spreader mechanism is located at one end of thedevice, the first and second arms, when moved to their extendedposition, enable the surgeon to view the cavity directly through theopening. A primary benefit of designing the support channels to engagetissue below the skin layer (e.g., the patient's breastbone) is that theincision can remain small (e.g., 5 cm). It is certainly contemplated, aswitnessed by the embodiment of the device 30 shown in FIGS. 4A and 4B,the spreader mechanism (i.e., central body 32) may be disposed withinthe opening under the skin layer. However, the surgeon, when employingthis type of device, must work around the spreader mechanism.

In one embodiment, the device 100 or 140 may include a mount 152 formedon the spreader mechanism 122 or 146 to mount the device on a supportassembly. As shown, such a mount 152 is provided on the underside of thespreader mechanisms 122, 146. FIGS. 13 and 14 illustrate a supportassembly, generally indicated at 160, that is integrally formed as partof an operating table 162. As shown, the operating table 162 includes apair of rails 164, 166 and a slider 168 that is designed to slide alongthe lengths of the rails. A locking mechanism (not shown) may beprovided to lock or otherwise secure the slider 168 in place. A supportarm 170 is attached at one of its ends to the slider 168, the supportarm 170 being configured to extend over the operating table 162 so thatit is positioned above the patient. The other end of the support arm 170is inserted into or otherwise connected to the mount 152 to secure thedevice 100 or 140 to the support arm. The arrangement is such that thedevice 100 or 140 may be slid along the length of the rails 164, 166 toposition the device at any position over the patient. The support arm170 may be telescopic, for example, so that the device 100 or 140 may bemoved laterally with respect to the patient. Although FIGS. 13 and 14illustrate the device 140, it should be understood, based on theforegoing description, that device 100 may be secured to the support arm170 as well via mount 152.

In one application using the device, an access incision is created overthe lower third of the breastbone longitudinally, and through it,tissues are dissected and the breastbone is completely divided with astandard jigsaw. As discussed, the device is modular in construction,and, in one embodiment, includes support channels with the C-shapedsurfaces that are configured to contact and divide the breastbone.Reference may be made to FIG. 15, which illustrates the two supportchannels 106 engaging a divided breastbone 180 below the skin layer 182.In one embodiment, the support channels 106 are between 5 and 12centimeters long. Two of these support channels, one for eachhemi-sternum, are inserted into the access incision, and are directlyapplied to the split breastbone 180 longitudinally. As described withreference to devices 100 and 140, the remaining part of the device haslong slender distracter shafts. With the device in the retracted,non-deployed position, the distracter shafts are inserted into asurgically created drain site or sites below the access incision andadvanced to engage the two breastbone support channels. In thisembodiment, the leading edges of these channels are pointed to allow fora wedge effect in distracting the breastbone 180. The distracter shaftsare connected to the actuator arms, which, depending on the device, maybe straight, curved, or of any other shape. The actuator arms are drivenby the spreader mechanism that has a gear box provided in a casing orhousing. The gear box in this example may be hand powered by a handcrank or a fluted thumb knob. In other embodiments, any suitableergonomic device may be provided to allow the operator to distract thesupport channels with minimal effort. Integral with the casing of thespreader mechanism may be low friction guide shoes that allow either theactuation arms to pass through with low friction. There may be furtherprovided assembly covers for the actuator arms to prevent trauma to theskin layer.

In certain embodiments, it is envisioned that the mount 152 may beadjunctively provided to enhance efficiency of the device. In oneembodiment, the mount 152 affixes the device to the operating table 162by securing the device to the support arm 170, which is slidably mountedon the operating room table by slider 168. This arrangement is designedto stabilize the device as the split breastbone 180 is distracted orseparated. The mount 152 is designed to permit mobilization and fixationof the device at differing angles from its insertion angle. Thisconfiguration is intended to offset discrepancies in the angle at whichthe divided breastbone 180 is spread due to asymmetries in either thedevice or in the patient's body. In addition, the mount 152 may havefurther attachments to expand the device's capabilities to provide sitesof fixation for stabilizing devices for beating heart surgery, or forhardware designed to distract the access incision to place it overdifferent areas of interest and facilitate surgery, for example.

It is envisioned that a fiber optic carrier (e.g., cabling) may beincorporated into the actuator arms, and contiguously through thedistracter shafts so that they may engage a light delivery system builtinto the breastbone support channels. This construction enables thesurgical field to be lit from within opening, as opposed to directinglight from outside the incision towards the deeper surgical field.

Similarly, video channeling or cabling may be built into the same abovestructures, with a video camera built into one or both the breastbonesupport channels to allow for live video of the surgical field forassistance during surgery or for recording and editing purposes. It thisexample, hardware for both light and/or video probes would attach to anappropriate portion of the actuation arms from a source off of theoperating room table, as is done commonly for standard videoscopicprocedures. In an alternate embodiment, the light and video optic cablecould be connected to the breastbone support channels directly (withoutchanneling through the actuator arms and distracter shafts, possiblythrough a one of the drain site incisions or another separatecounter-incision.

In addition, separate hollow channels bored contiguously through theactuation arms and distracter shafts could be used for deliveringsterile gas, such as carbon dioxide (CO₂), deep into the surgical fieldfrom a source off of the operating table, for example. CO₂ may be usedin open heart surgery to displace air, as CO₂ is readily absorbed inblood, and air can cause “gas embolism,” with undesirable consequences.Directed blasts of CO2 can also be used to displace blood from surgicalareas of interest during coronary surgery, for example.

FIGS. 16 and 16A show a nested configuration of a device having twoL-shaped actuators 118, 120, which are attached to arms 102, 108,respectively. The arms 102, 108 may be fixed to, or reversibly attachedto support channels 106. A spreader mechanism 146, which may embody oneor more gears that are driven in a rack-and-pinion fashion, drives themovement of the actuators 118, 120 to spread the arms 102, 108 apart toan extended position. As shown, each actuator 118, 120 includes teethprovided on one side of the actuator to engage gears of the spreadermechanism. In a retracted (closed) position, the arms 102, 108 and theactuators 118, 120 are configured such that they form one L-shapedmember that is adjacent to and positioned within a second L-shapedmember, when viewed in FIG. 16. It should be understood that althoughboth actuators 118, 120 are coupled to the spreader mechanism 146 tomove the arms 106, 108 apart from one another, the spreader mechanismmay be configured to drive the movement of one actuator (118 or 120)with the other actuator being fixed to the spreader mechanism or someother support. In such an embodiment, only one actuator (118 or 120)would require teeth formed on the side of the actuator.

FIG. 17 shows another embodiment of a device having arms 102, 108 thatare attached to actuators 118, 120 respectively. As shown, a segment 184of one of the arms (arm 108) overlies actuator 118. It should beunderstood that a segment of one of the arms may be configured tounderlay an actuator in other embodiments of the device.

FIG. 18 illustrates another embodiment of a device having a doublespreader mechanism design. As shown, the device includes two spreadermechanisms, each indicated at 193, attached to opposite sides 168 of anoperating room table 162 by a support bracket 192. In one embodiment,each spreader mechanism 193 in this iteration is a pulley, which areattachable to cables 187, 188. Alternatively, the spreader mechanism maybe configured to operate only one cable. Cables 187, 188 are attached toor reversibly attached to one or more locations 185, 186 provided on thesupport channels 106. A different support channel 189 may be providedthat has a wide portion 190 and a narrow portion 191, which may beadvantageous to this design to prevent slippage from the dividedbreastbone edge while the pulley mechanism is actuated.

FIGS. 19 and 19A show another embodiment of a device that is meant to beplaced completely underneath the skin layer when a tissue plane andspace is developed between adjacent muscle and subcutaneous fattytissue. Arms 102, 108 are either reversibly attachable to supportchannels 106 or permanently attached to support channels 194. Arm 102 isattached to a base 195, which has an opening 196 configured to have aninternal thread so as to threadably receive (in a nut-and-bolt fashion)a threaded actuator 197. Arm 108 is connected at one end 202 to theactuator 197. The end 202 of the arm 108 includes a freely spinningwasher (not shown) so that when the actuator 197 is turned by a crank201, the arm 108 is not turned in conjunction with the actuator.Instead, turning the actuator 197 by using the crank 201 causes the arms102, 108 to extend apart from one another in a common (e.g., horizontal)plane. The actuator 197 may be larger than ¼-inch in diameter in orderto accommodate the load required for spreading apart resistant tissue.The crank 201 may have a joining tip 200 that fits into a socket 199 ofthe actuator bolt head 198. When the crank 201 is turned in the oppositedirection, the arms 102 and 108 are retracted back to a collapsedposition. Typically, with the device completely underneath the skinlayer, crankshaft 201 is placed via a separate stab incision (such asstab incision 24 shown in FIG. 2) in order to join the tip 200 and thesocket 204 in order to actuate the device and spread the arms 102, 108apart underneath the skin layer.

FIGS. 20 and 20A illustrate another embodiment of a device having adouble spreader mechanism design. Two spreader mechanisms, eachindicated at 193, are attached by support brackets 192 to the operatingroom table 162 at opposite sides 168. In one embodiment, the spreadermechanisms 193 may be reversibly attachable to opposite sides 168 of theoperating room table 162 at predisposed locking points. In this design,the actuators 118, 120 are connected to arms 108, 102 respectively, andare configured generally as mirror-image L-shaped members. In thisdesign, the actuators 118, 120 have gear teeth, and spreaders 193 may beused as a rack-and-pinion design in order to extend the arms 102, 108apart. Alternatively, the arm-actuator complexes could be configured asmirror-image T-shaped members.

FIGS. 21 and 21A show another embodiment of a device that is meant to beplaced completely underneath the skin layer when a tissue plane andspace is developed between adjacent muscle and subcutaneous fatty tissuelayers. Arm 102 is attached to or reversibly attached to support channel106 at one end, and to actuator 120 at its other end. Actuator 120passes through base 203, with the base being attached to arm 108, whichin turn is attached to or reversibly attached to support channel 106.Base 203 contains at least one or more gears 205, 206. Gear 205 has asocket 204 into which a crankshaft 201 fits into at its end 200.Crankshaft 201 may be attached to a reversibly attachable to base 203 byadjoining portions 200, 204. When crankshaft 201 is turned, gear orgears 205, 206 interact with the gear teeth of the actuator 120, causingthe arms 102 and 108 to extend apart from one another. When crankshaft201 is turned in the opposite direction, the arms 102, 108 are retractedback to a collapsed position. Typically, with the device completelyunderneath the skin layer, crankshaft 201 is placed into a separate stabincision 24 (FIG. 33) in order to join end 200 with socket 204 in orderto actuate the device and spread the arms 102 and 108 apart underneaththe skin layer.

FIG. 22 represents another embodiment of a support channel 106 having alight panel 207 that is built into an undersurface of the channel 106.The light source may be fiber-optic, which originates from a generator210. The light source is delivered through a cable 209 to a connector208, which is connected to a receptor socket 211. Alternatively, lightpanels 207 may be powered by batteries 212 integrated into supportchannels 106. The lighting may be comprised of light emitting diodes(LEDs), or any other suitable light source. The lighting is located onan undersurface 215 of the support channels 106 so that light 213 can bedirected below the device when viewed from above. Although shown onundersurface 215, the lighting may be provided on any part of thesupport channel 106 suitable for illuminating a desired area of apatient.

Referring now to FIGS. 23-33, a method of performing surgery isdiscussed. FIGS. 23 and 23A illustrate the initiation of the method ofperforming surgery through a small skin access incision 20, which may be8 cm or smaller. The small access incision 20 shows the layers of softtissue between the skin 20 and the underlying bony tissue barrier, inthis case, the breastbone 218. From external to internal, the accessincision layers include skin 20 and fatty tissue 216. Also seen throughthe small access incision 20 is underlying muscle 217.

FIGS. 24 and 24A show next steps of the method. A soft tissue rake 219is used to lift skin 20 and fatty tissue 216 up and away from the musclelayer 217. Both blunt dissection and an electrocautery pen 220 are usedto separate the normally adherent fatty tissue and muscle layers.

FIGS. 25 and 25A show further progression of the method by extending thedissection between the fatty tissue 216 and the muscle layer 217 to amuch larger space 222 radiating in all directions from the small accessincision 20. This is accomplished using surgical retractors 221 and anelectrocautery 220, as well as blunt surgical dissection.

FIGS. 26 and 26A illustrate that after creating the large space underthe fatty tissue layer 216, the small access incision 20 becomes quitemobile, and can be manipulated with the surgical retractor 221 in orderto gain access to the entire length of breastbone 218 and overlyingmuscle layer 217. Pectoralis muscle 217 is divided longitudinally alongline 223 from its superior to inferior margin, thereby exposing thebreastbone underneath.

FIGS. 27 and 27A illustrate the use of a standard surgical jigsaw 224and a blade 225 used to divide longitudinally breastbone 218 through thenow mobile access incision 20. The surgical retractor 221 is used topull traction up or down on access incision 20 in order to expose theupper and lower portions of breastbone 218 to facilitate division.

FIG. 28 shows the completely divided breastbone 218, and the space 226in between the divided edges, visible through the access incision 20.Also shown are smaller stab incisions 24 that are distinct from accessincision 20.

FIG. 29 illustrates the insertion of a specialized device created forthe method in which the arms 102, 108 are inserted through the distinctstab incisions 24, and advanced towards access incision 20 and intoview. At this stage, actuators 118, 120 are external to the skin.

FIGS. 30 and 30A are enlarged views of arms 102, 108 that have beeninserted through distinct stab incisions 24. In this iteration, supportchannels 106 are slid onto arms 102, 108 through the access incision 20.Support channels 106 are applied to the divided edges of breastbone 218to prepare the device for deployment.

FIGS. 31 and 31A show an iteration of the device in partial stages ofdeployment. As the hand-crank 124 of the spreader 134 is turned, theactuators 118, 120 are advanced underneath the skin into the createdspace by access through the distinct stab incisions 24. In thehalf-deployed position, portions of the actuators 120, 118 are externalto the skin, while other portions are underneath, internal to the skin227, 228, respectively. As the spreader is actuated, the arms 102,108and the support channels 106 spread the divided edges of the breastbone218 apart to create an access space to the deeper tissues 226, whichgets larger as the device is expanded.

FIG. 32 illustrates an iteration of the device in a completely extendedposition. The majority of actuators 118, 120 are now underneath the skinlayer, as actuators 227, 228, having been advanced by spreader 134 byaccess through the distinct stab incisions 24. The attached arms 102,108 and the support channels 106 extend the divided breastbone edges 218apart. Because the divided breastbone is spread far apart, the surgeonnow can visualize and manipulate typical structures such as the heart,lungs and aorta through access incision 20.

FIG. 33 is an illustration of a different device, such as the deviceshown in FIG. 19, in the completely deployed (extended) position. Thedevice is positioned below the skin and fatty tissue layer aftercreating the space by the method described. The crankshaft 201 is placedthrough the distinct stab incision 24 in order to join actuator bolt197, and drive it through base 195. The crankshaft 201 can then beremoved from actuator bolt 197 during the procedure. In the extendedposition, the attached arms 102, 108 and the support channels 106 spreadapart the divided breastbone edges 218 in order to maintain deep accessspace 226, and allow visualization of deep structures through the accessincision 20. At the end of the procedure, the crankshaft 201 is turnedin the reverse direction to collapse the device to facilitate removal.

FIG. 34 illustrates a device 300 of another embodiment. As shown, thedevice 300 includes a spreader mechanism 302 having a base 304 and ahandle 306. The device further includes an actuator 308 that extendsthrough the base 304 of the spreader mechanism 302. The rotation of thehandle 306 of the spreader mechanism 302 causes the relative movement ofthe actuator 308 with respect to the base 304. As shown, the spreadermechanism 302 further includes another actuator 310, which is fixedlysecured to the base 304. Arms 312, 314 are attached to respectiveactuators 308, 310, with each actuator being curved when transitioningto its respective arm. As shown, actuator 308 overlies arm 314. However,it should be understood that the device 300 may be configured so thatarm 314 overlies actuator 308 and fall within the scope of the presentdisclosure.

In this example, one of the actuators (e.g., actuator 310) is fixed tothe base 304 of the spreader mechanism 302, and the other actuator(e.g., actuator 308) is comprised of both a curved segment as well as astraight segment containing gear teeth 316. In another embodiment, bothactuators may be configured to have curved and straight segments withgear teeth, and the spreader mechanism is configured to engage eachactuator. The spreader mechanism 302 includes gearing or any suitablemechanism provided within the base 304 to actuate the movement of theactuator 308 when turning the handle 306.

Embodiments of the device disclosed herein may be utilized to perform anumber of surgical procedures. For example, in a method for performingsurgery on organs located below a skin and muscle layer through a smallskin incision, the method comprises: making a small access incision inthe skin; surgically separating a tissue plane between a normallyadherent and adjacently layered muscle and fatty tissue radiatingoutward from the skin; utilizing a device to spread divided deepertissues apart below the level of the skin without directly contactingthe skin edges of the access incision; and performing a surgicalprocedure. In one embodiment, the small access incision is generallyless than 8 cm long. The device may be configured with a crankshaftdriver that traverses from external to, to internal to, the skin inorder to actuate and spread the device apart below the intact skinadjacent to the access incision.

In another example, a method for performing heart surgery through asmall skin incision comprises: making a small access incision in theskin overlying the breastbone; surgically separating a tissue planebetween the normally adherent and adjacently layered pectoralis muscleand fatty tissue radiating outward from the skin incision underneathadjacent areas of intact skin; dividing the pectoralis muscles and thebreastbone vertically in the midline; utilizing a device to spread apartthe breastbone below the level of the skin without directly contactingthe skin edges of the access incision; and performing heart surgery. Inone embodiment, the small access incision is generally less than 8 cmlong. The device may be configured with a crankshaft driver thattraverses from external to, to internal to, the skin in order to actuateand spread the device apart below the intact skin adjacent to the accessincision.

In another example, a method for instructing a surgeon to perform heartsurgery through a small skin incision comprises: directing the surgeonto create a small access incision in the skin overlying the breastbone;surgically separating the tissue plane between the normally adherent andadjacently layered pectoralis muscle and fatty tissue radiating outwardfrom the skin incision underneath adjacent areas of intact skin;dividing the pectoralis muscles and the breastbone vertically in themidline; utilizing a device to spread apart the breastbone below thelevel of the skin without directly contacting the skin edges of theaccess incision; and performing heart surgery. In one embodiment, thesurgeon is further instructed to actuate the device by utilizing acrankshaft driver that traverses from external to, to internal to, theskin.

In a further example, a method for instructing a surgeon to performsurgery through a small skin incision comprises: directing the surgeonto create a small access incision in the skin overlying the region ofinterest; surgically separating the tissue plane between the normallyadherent and adjacently layered muscle and fatty tissue radiatingoutward from the skin incision underneath adjacent areas of intact skin;dividing the muscle layer; and utilizing a device to spread apart thedeeper tissues below the level of the skin without directly contactingthe skin edges of the access incision, and performing a surgicalprocedure. In one embodiment, the surgeon is further instructed toactuate the device by utilizing a crankshaft driver that traverses fromexternal to, to internal to, the skin.

Having thus described several aspects of at least one embodiment of thisdisclosure, it is to be appreciated various alterations, modifications,and improvements will readily occur to those skilled in the art. Suchalterations, modifications, and improvements are intended to be part ofthis disclosure, and are intended to be within the spirit and scope ofthe disclosure. Accordingly, the foregoing description and drawings areby way of example only.

1. A method of performing an open heart surgery procedure, the methodcomprising: making a small incision in a skin layer above a breastboneof a patient; dividing the breastbone to create an opening below theskin layer; inserting arms of a device into at least one surgicallycreated site, the at least one surgically created site being separatefrom the small incision; advancing the arms underneath the skin layer toengage sides of the opening; expanding the device to increase theopening; performing a medical procedure; retracting the device; andclosing the opening.
 2. The method of claim 1, wherein expanding thedevice includes moving at least one arm of the device to widen theopening.
 3. The method of claim 1, wherein the device is configured towiden the opening below the skin layer without widening the opening ofthe skin layer beyond the small incision.
 4. A method of performingsurgery, the method comprising: making a small incision in a skin layerof a patient; dividing tissue underneath the skin layer to create anopening; inserting arms of a device into at least one surgically createdsite, the at least one surgically created site being separate from thesmall incision; advancing the arms underneath the skin layer of thepatient to engage sides of the opening; expanding the device to increasethe opening; performing a medical procedure; retracting the device; andclosing the opening.
 5. The method of claim 4, further comprisingretracting the device and closing the opening.
 6. The method of claim 4,wherein the device is expanded to spread apart the breastbone up to 20cm.
 7. The method of claim 4, wherein the device is configured to widenthe opening below the skin layer without widening an opening of the skinlayer beyond the small incision.